This invention relates generally to batch-casting mold table assemblies, and more particularly to a hydraulically driven mold table assembly for producing slabs having a smooth surface finish.
Batch cast slabs made of copper alloys such as brass are formed by pouring molten metal through a mold. After passing through the mold, the slabs are cooled in a fluid-filled pit located beneath the mold. Frequently, these slabs are further processed into sheets by repeatedly passing them between rollers and incrementally reducing the distance between the rollers. To obtain sheets having a good surface finish, the slabs from which the sheets are formed must have a good surface finish. Slabs having a good surface finish may be made by oscillating the mold up and down as the molten metal passes through it. The optimal speed(s) at which the mold is oscillated up and down varies depending upon the particular physical and metallurgical properties of the metal being poured and the characteristics of the mold. Methods for determining these optimal speeds are well known by those skilled in the art.
Mold tables having mechanical linkages such as cams and/or four-bar linkages have been used to oscillate the molds up and down. However, these linkages are susceptible to wear and do not permit the oscillatory speed(s) of the mold to be changed easily. Moreover, these linkages do not permit the speed at which the mold moves up to be changed independently of the speed at which it moves down without modifying the linkages themselves (e.g., by changing the cam shapes). Further, previous mold tables have not been adapted to permit quick mold changes.